Telephone system



.(No Model.)

R. N. DYBR.

TELEPHONE SYSTEM.

No. 481,483. A Patented Aug. 28, 1892.

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UNITED STATES PATENT OEEICE.

RICHARD N. DYER, OF EAST ORANGE, NEW JERSEY, ASSIGNOR TO THE AMERICAN BELL TELEPHONE COMPANY, OF BOSTON, MASSACHUSETTS.

TELEPHONE SYSTEM.

SPECIFICATION forming part of Letters Patent N o. 481,483, dated August 23, 1892.

Application filed October 30, 1890. Serial No.369,804. (No model.)

.To all whom it may concern: erence to the electro-motive force of the cir- Be it known that I, RICHARD N. DYER, a cuit 1 2. citizen of the United States, residing at East In order that the circuit 3 4 should never Orange, in the county of Essex and State of be directly connected with the telephone-line,

5 New Jersey, have invented a certain new and while at the same time it is opened and closed 5 5 useful Improvement in Telephone Systems, by the telephone-switch, so as not to be using of which the following 1s a specification. current when the telephone is out of use, I My invention relates to the telephone sysprefer that the points c should not touch tem described in my patent, No. 382,461; and' the body of the switch A, but should bear to my object is to improve the manner of Aconupon a plate f, which is carried bythe switch, 6o

necting the telephone and signaling devices but is insulated therefrom by a block g of inwith the current-supplying circuit or source sulating material. By this means the disof electrical energy, whereby great efficiency turbances which would arise from grounding in operation and simplicity in construction the circuit 3 4 will be avoided; or, as shown in r 5 are secured and so that the disturbances and Fig. 2, the circuit 3 4 can terminate in spring- 65 dangers arising from grounding the currentplates Z9 c', which spring together and close supplying circuit through the telephone apthe circuit 3 4 when the switch is raised, but paratus or line are avoided. are separated by a plate g of insulating ma- In the drawings, Figure 1 is a view in diaterial when the switch is depressed. The

zo gram 'showing apparatus and circuits emplate g is carried bythe switch and is forced 7o bodying the invention. Fig. 2 is a view of a between the spring-plates h c', not only sepmodiiied form of the telephoneswitch. Fig. arating such plates, but cutting off anyspark 3 is a separate view of a special form of bellor arc, the insulating-plate being wider than ringing device. the metal plates.

z 5 The current-supplying circuit 1 2 is repre- In either side of the circuit 3 4 is a deter- 75 sented as a lamp-circuit of a system of elecmining-resistance h, around which is a shunttric lighting, in which incandescent electric circuit 5 6, in which are located the telephonelamps are shown at a. The electric lighting transmitter C and the primary of the usual system may be a simple multiple arc, threeinduction-coil D. The resistance h will be 3o wire, or other system employing continuous proportioned with relation to the other ele- 8o currents. From the circuit or loop 1 2 is taken ments of the circuits 3 4 and 5 6, as will be a multiple-arc circuit 3 4, the two sides of well understood, so that the desired quantity which terminate at two of the upper points b of current will Iiow through the transmitterc of a four-point telephone-switch A, the circircuit. The telephone-line 7 is connected 35 cuit 3 4 being completed at the points b c with the switch A. The third upper point 85 when the switch is raised and being opened of the switch is connected by a wire 8 with at those points when the switch is depressed the earth E through the secondary of the by hanging the receiver upon its hook, so as induction-coil I) and the telephone-receiver not to use current when the telephone is out F. This completes the telephone apparatus 4o of use. A magnet B has its coils d e located proper. 9o in the circuit 3 4, one of these coils being For receiving and sending call-signals the preferably in each side of the circuit, so as to following arrangementis provided: The lower reduce the liability to the formation of inj upoint 7a of the switch is connected by a Wire rious grounds and crosses. This electro-mag- 9 with the earth E through the vibrating bell 45 netic or inductive-resistance acts by resist- G and through one or more coils Z uponthe 95 ance and self-induction to reduce and steady magnet B. When the receiver is hung on the the current flowing from the supply-circuit switch, the line will be completed t0 earth through the loop and transmitter, and for through the bell and call-signals can be resaid purpose this resistance is properly proceived, as usual heretofore. For sending sig- 5o portioned, as will be well understood with refnals I provide a means for making and breakroo ing the circuit 3 4E through the coilsd e ofthe magnet B, which then become primary coils, producing induction impulses in the secondary coils l and sending them out over the line. To make and break the circuit through the coils d e, I may employ a normally-open spring key or lever m, which in its forward movement makes contact with a spring-lever n and moves it off of a point o. The key m and point o are connected across the circuit 3 4 between the coils d c and the resistance h. The key or lever m thus both makes and breaks the circuit through the magnet-coils in its forward movement and resumes a position in which the circuit is open. The operation does not alfect the transmitter. To secure a continuous vibration, the lever m may be moved "by a wiper-wheel 1o, rotated by a crank q, as shown in Fig. 2. As shown in Fig. l, a shunt 12, provided with a push-button for opening the same, may be extended across the two sides leading to and from coils Z l, so that said coils will be short-circuited when not actually in use for signaling. By producing the signal impulses by induction from the current-supplying circuit or source of electrical energy the direct connection of that circuit with the telephone-line becomes unnecessary. The magnet-coils d e not only serve to reduce the current flowing in the circuit 3 4, as Well as to act as the primary for the induction-signal impulses, but they further act advantageously in the operation of the telephone-transmitter by exerting a retarding influence upon vibrations of the current passing through the circuit 3 4, and thus render such vibrations incapable wholly or partly of affecting the transmitter and producing disturbing sounds in the receivers.

For the better protection of the telephone apparatus the circuit 3 4 is provided with a suitable safety-catch link r in each side of the circuit.

l. The combination, in a telephone sub-station apparatus, of a telephone-transmitter, a current-supplyingcircuittherefor,anormallyopen loop from said supply-circuit to the said transmitter, a resistance in a shunt-circuit of the said loop around the transmitter, acircuit-closer controlled by the automatic telephone-switch and acting, as the telephone is removed from or replaced on its support, to close or open the loop-circuit through the transmitter, and an electro-magnetic resistance included directly in the loop-circuit and acting as its resistance and self-induction to control the strength and steady the current iowing through said loop and transmitter, substantially as described.

2. The combination, with the telephonetransmitter, of a current-supplying circuit therefor, a loop from said supply-circuit to the transmitter and including the same, an electro-magnetic resistance in the said loop, constituting, also, the primary helix or helices of an induction-coil for sending call-signals, and a circuit-controller for alternately making and breaking the circuit of the loop at a point between the transmitter and the said electromagnetic resistance.

3. The combination, with a telephone-transmitter, of a current-supplying circuit, a branch or loop circuit therefrom extending to said transmitter, a controlling and steadying electro-magnetic or inductive resistance in said branch circuit the helices of which also constitute the primary helix or helices of an induction-coil for sending call-signals, and a determining-resistance included in a shunt of said loop-circuit around the transmitter, substantially as set forth.

4. In combination with the mains of a constant-direction electric-light or power circuit, a telephone-transmitter, a loop from said mains to the said transmitter, a steadying and current -regulating electro magnetic resistance included in said loop, a safety-catch interposed in said loop between the said resistance and the main-line junction, and a determining-resistance in a shunt of said loop uniting the transmitter-terminals, substantially as set forth.

5. The combination, with a telephone, of a current-supplying circuit, a branch therefrom supplying the transmitter, current-reducing magnet-coils located in said branch, secondary coils upon such magnet connected with the line through the bell-circuit, and a key closing the branch circuit through the magnetfcoils and not through the transmitter, substantially as set forth.

6. The combination, with a telephone, of a current-supplying circuit, a branch therefrom supplying the transmitter, current-reducing magnet-coils located in said branch, secondary coils upon such magnet connected with the line through the bell-circuit, a key closing the branch circuit through the magnet-coils and not through the transmitter, and the telephone-switch opening and closing the branch circuit Without grounding the same,-

substantially as set forth.

This specification signed and witnessed this 13th day of October, 1890.

RICHARD N. DYER.

Witnesses:

D. H. DRIscoLL, E. LoURAN.

IIO 

